Snap-lock container ring and method

ABSTRACT

The present invention is directed to a carton including a lid and a container having a reinforcing ring that cooperatively engages the top portion of the container in a rib-and-groove snap-lock fit. The reinforcing ring is coextensive with the opening of the container and has a band located on the interior of the container, and exposes no sharp edges. The ring is butted against the inside of the container wall and the top edge of the container wall. An edge of the ring lies on the top edge of the container wall and is inwardly recessed from the wall thus preventing the ring from protruding beyond the container wall and eliminating interference with adjacent containers or the risk of injury to fingers or hands.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

BACKGROUND OF THE INVENTION

The present invention relates generally to containers and more particularly to an improved construction for a ring or rim used to reinforce and protect the upper edge of a large paperboard container particularly useful for food such as ice cream.

Paperboard containers are used in a variety of packaging applications, including the packaging of foods. Such a container can have a generally round mouth and can also have a general cylindrical sidewall. Relatively large diameter paperboard containers having a large capacity, several gallon capacity for example, are widely used to package food products in bulk quantities. In some cases these containers are also used on an ongoing basis to store and dispense the food product, such as in the case of the retail sale of ice cream. The edges of these large containers are susceptible to being dented, frayed and torn and are typically lacking in hoop compression strength or bending resistance at the open mouth. To address this issue, a metal reinforcing ring is ordinarily applied to the upper edge of the container to provide it with the necessary strength or bending resistance and protection to prevent the deterioration of the container opening.

These metal reinforcing rings that have been used in the past are applied to the container by crimping rolls that roll a portion of the ring over the top edge of the container. The ring is held in place on the container by an edge of the rolled portion which bites into the container wall. The ring extends along the inside surface of the container and terminates in a lower edge which lies against the inside surface of the container wall. Although this type of reinforcing ring functions well to strengthen and protect the edge of the container, it has not been entirely satisfactory in all respects. Other types of rings with varying configurations and methodologies for crimping, curling and curvature of the edges have also failed to be satisfactory in similar respects.

Most notably, the lower edge of the ring may present an exposed edge which can cut the fingers, hands or arms of persons reaching into the container. In addition, the manner in which the ring is fastened on the top of the container is lacking. The fastened ring has an edge that protrudes beyond the outside surface of the side wall of the container, thus creating an outer lip that can catch on other containers or objects placed adjacent to the container. As a result, apart from the inconvenience encountered in the placement of the container, the ring can also become dislodged or torn away from the container. The loss of the ring detracts from the structural integrity of the upper rim area of the container. A metal ring can also be permanently deformed.

There is therefore a need for a container construction with a top ring that provides versatility by reinforcing and protecting the upper edge of a container, while presenting less of a permanent deformation potential or hazard to persons who reach into the container. Even further there is a need for a ring that is easily installed, and the presence of which will not adversely impact the placement of the container in close proximity to other containers or enclosures.

SUMMARY OF THE INVENTION

The present invention addresses these needs and overcomes the limitations of the prior art. More specifically, the present invention is directed to an improved ring which is applied to the container in a manner to reduce exposed sharp edges and deleterious surfaces or edges. The ring is also held in place more securely and with less manufacturing effort, than the metal rings that have been used in the past. In a preferred embodiment, the ring does not appreciably protrude beyond the sidewalls of the container and thus does not interfere with the container placement or present the risk of having the ring detached from the container.

The present invention provides, among other things, a reinforcing ring partially located over a container edge, the ring cooperatively engaging the top portion of the container in a rib and groove snap-fit mechanical interlock. The container has a side wall with a top portion and a bottom portion, wherein the top portion defines an open mouth. The top portion of the container has a folded edge that forms an internal downwardly facing shoulder extending around the interior perimeter. The bottom portion of the side wall has a folded edge that is attached and preferably sealed to a depending skirt of a bottom wall to form a container bottom.

The reinforcing ring has a through opening coextensive with the opening of the container side wall. A portion of the ring rests against the inside surface of the container side wall creating a reduced diameter neck with an exposed band portion. The band portion of the ring, located on the interior of the container exposes no sharp hazardous edges.

The ring is butted against the inside of the container side wall and the top edge of the container wall. The edge of the ring that lies on the top edge of the container side wall is located such that the ring does not protrude appreciably beyond the container side wall and is thus not susceptible to catching on adjacent containers, cutting or otherwise injuring persons.

Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is further described with reference to the accompanying drawings, which show various constructions and implementations of the present invention. However, it should be noted that the invention as disclosed in the accompanying drawings is for illustrative purposes only. The various elements and combinations of elements described below and illustrated in the drawings can be arranged and organized differently to result in constructions which are still within the spirit and scope of the present invention. The accompanying drawings form a part of the specification and are to be read in conjunction therewith and in which like reference numerals are used to indicate like parts in the various views:

FIG. 1 is a perspective view of a paperboard container equipped with a polymeric ring applied to the top portion of the container in accordance with an embodiment of the present invention;

FIG. 2 is a cross-sectional view of the container shown in FIG. 1 but without the ring;

FIG. 3 is an enlarged fragmentary sectional view of a portion of the container and the ring shown in FIG. 1;

FIG. 4 is a top plan view of the ring of the present invention;

FIG. 5 is a bottom plan view of the ring of the present invention;

FIG. 6 is a cross sectional view of the ring and

FIG. 7 is an enlarged fragmentary cross-sectional view of the ring.

DETAILED DESCRIPTION

The detailed embodiment of the present invention is described herein. It should be understood, however, that the disclosed embodiment is merely exemplary and that the invention may be embodied in a variety of forms. Therefore, the illustrated drawings FIGS. 17 and description herein should not be construed to limit or otherwise set forth the scope of the invention but rather to provide a basis for the claims and to teach the making of an embodiment of the present invention.

Referring now to the drawings in more detail and turning initially to FIGS. 1 and 2, numeral 5 generally designates a carton of a type which may be used to package food items in bulk quantity such as ice cream. Such carton can be large enough to hold several gallons of product or many pounds. The carton 5 includes a container 10 that may be formed of any suitable material including metal, paper or plastic and may take on a variety of shapes and sizes. The embodiment of the invention described herein involves a container 10 formed with paper board. The container 10 as described herein has a wall structure which as shown has a generally cylindrical or tubular body, with an opening 13 at the top and a closed bottom 15. The carton 5 includes a lid 6 having a top closure panel 7 and a side skirt 8 that surrounds an upper portion of side wall 12. The lid 6 may be made of material similar to the side wall 12 as described below. The container base 10 has a generally cylindrical side wall 12 formed from paperboard or a similar material. There is a bottom wall 22 which is attached in any suitable manner to define a storage compartment. Further, the container 10 may also have the lid 6 fitted thereon and retained in place by friction and/or a tamper resistant closure as are known in the art. The container 10 includes a top portion 14, a bottom portion 16 and a reinforcing ring 26 located at the top portion 14. The ring 26, which will be discussed in greater detail later herein, provides compressive and tensile reinforcement to deformation of the opening 13 of the side wall 12 without presenting a hazard of injury to users of the container 10. The ring 26 and side wall 12 as shown in FIGS. 1 and 2 are cooperatively and preferably mechanically inter-engaged in a manner that is facilitated by novel features of the present invention. Specifically, there is a snap-lock engagement of a rib and groove located on either one of the side wall 12 or the ring 26 to effect mounting of the ring 26 to the side wall 12. The description that follows focuses on a configuration wherein the groove receives the rib therein, however, it should be understood, and it is contemplated, that other configurations can achieve the snap-lock connection.

Turning initially to further features of the container 10, FIG. 2 illustrates a cross-sectional view of the container 10, and some of the features therein. As shown, the top portion 14 of the side wall 12 is folded over inwardly and around the perimeter of the side wall 12 in a conventional manner to form a rib 17 (shown in FIG. 3) with a first shoulder 18 and a top rim portion 32 also forming a shoulder, the shoulders facing oppositely of one another. The shoulder 18 faces generally downwardly toward the bottom portion 16. In the illustrated embodiment of the invention, the bottom portion 16 of the container 10 is also folded inwardly and around the perimeter of the container 10 in a conventional manner, to form a u-shaped bottom groove 20. The generally circular bottom wall 22 includes a fold that creates a depending skirt 24. As shown, the skirt 24 is positioned within the groove 20. The skirt 24 is attached to the side wall 12 in the groove 20 on both side faces of the skirt 24 and the seam therebetween sealed in any one of several conventional manners, thereby attaching the bottom wall 22 to the side wall 12. As would be understood by one skilled in the art, the two portions may be sealed as with a bead of thermoplastic material or adhesive or sealed by other means, such as ultrasonic welding The side wall 12 and bottom wall 22 may be formed as an integral unit by injection molding. Regardless of the method utilized to form the side wall/bottom wall assembly, there is a resulting seal of the bottom wall 22 to the side wall 12 of the container 10 to define a storage chamber for receiving product therein. In some applications, a layer of material, such as a thermoplastic is applied to the inner surface and edges of the container wall 12 and the inner surface of the bottom wall 22. This added material traditionally prevents wicking of the contained substance into and possibly through the paper board of the container 10. The side wall 12 may be made of two layers of helically wrapped layers of paper board with one layer overlapping the edge seam or butt joint of the other layer.

Turning next to the features of the ring structure 26, preferably molded of a polymeric material, which is applied to the top portion 14 of the side wall 12 for the purpose of strengthening the top portion 14 and protecting the edge 32 of the side wall 12. The ring 26 defines a central opening or mouth 40. When the ring 26 is attached to the side wall 12, the mouth 40 is coextensive with the opening 13. It should be understood that the ring 26 may be made from any one of a number of materials having similar characteristics to a polymeric product and yielding similar handling safety, food safety, attachability, and formability. Generally, the ring 26 is formed from a suitable material such as polymer or other substances having adequate strength to reinforce the top portion 14 and upper edge, 32 of the side wall 12, and present non-cutting edges in the normal use. The ring 26 is best described with reference to FIGS. 4 and 5.

FIG. 4 illustrates a top plan view of the ring 26. FIG. 5 illustrates the bottom plan view of the ring 26 and shows a plurality of cavities 48 between inner and outer axially aligned rings, the inner ring being referred to as ring or band 44 and the outer ring including skirt 34 and a plurality of webs or brace portions 46 alternately located around the inner perimeter of the skirt 34. The cavities 48 are separated by webs 46 extending between band 44 and skirt 34. In the illustrated embodiment of the present invention, a material conservation technique is implemented wherein instead of providing a solid thick band 44, a thinner layer of plastic is utilized in conjunction with the webs 46 to provide adequate rigidity for the ring 26, while reducing the amount of material required to form the ring 26.

FIG. 6 illustrates a cross-section of the ring 26. FIG. 7 further illustrates an enlarged view of the ring 26 and the details of the construction of an embodiment of the present invention. As shown, the ring 26 comprises the interior peripheral band 44 forming a perimeter of the mouth 40 and, as shown, a round opening, and has a surface 43 slightly downwardly and inwardly inclined from a generally horizontal top ledge 42. As used herein, vertical and horizontal orientations are based on the container 10 being in its normal upright orientation. The ledge 42 is in turn adjacent to an outwardly extending flange 28 and faces generally upwardly. The flange 28 forms a downwardly facing shoulder 30. Adjacent to the shoulder 30 and radially inward of the flange 28 is a peripherally and preferably circumferentially extending and depending skirt 34. Extending radially outwardly of the skirt 34 is a flange 36, which extends around the perimeter of the skirt 34. The flange 36 has an upwardly facing shoulder 38 also extending preferably around the entirety of the skirt 34. It should be understood that either or both of the flanges 28, 36 may extend around the entire perimeter of the ring 26, or a portion thereof so long as a seal is formed between the ring 26 and the side wall 12 and securement of the ring 26 to the side wall 12 can be effected. Consequently, the shoulders 30, 38 may also be continuous or non-continuous around the perimeter of the ring 26.

In the embodiment described herein, the combination of the skirt 34, shoulder 30 and shoulder 38 define a peripheral and preferably circumferential groove 52. The earlier described cavities 48, are defined by the band 44, the top ledge 42 and the anterior side of the skirt 34 along with the webs 46, which are peripherally interspersed throughout. The webs 46 provide a support between the band 44 and the anterior side of the skirt 34, and help rigidify the ring 26 against radial compression or tension deformation of the ring 26 and side wall 12. Importantly, the band 44 and ledge 42 present non-cutting edges and thus reduce the risk of a cut to a person reaching into the container 10. Having thus described the ring 26 and its various features as well as those of the container 10, we turn next to the cooperative combination of the two pieces, which is best described by reference to the illustration of FIG. 3

In FIG. 3, a cross-sectional view of the side wall 12 and ring 26 of the present invention is illustrated. In operation, and as shown, the ring 26 cooperatively engages the top portion 14 of the side wall 12. When installed, a portion of the ring 26, specifically the shoulder 30, rests upon the edge 32, which functions as a shoulder, of the container 10 limiting relative axial movement of the ring 26 to side wall 12 in one axial direction. Another portion of the ring 26, the circumferential groove 52, cooperatively receives the rib 17 and the shoulder 18 therein. This locates the shoulder 38 below the shoulder 18 to effect the snap lock mounting.

The ring 26 is attached in a cooperative snap-lock rib-and-groove inter-engagement with the side wall 12. In the embodiment of the invention described herein, there is a cooperation of the surfaces defining the circumferential groove 52 (as shown in FIG. 7) of the ring 26 and the rib 17 of the side wall 12. The shoulder 38 engages the shoulder 18 to secure the ring 26 in place and to the side wall 12 in a mechanical manner eliminating the need for crimping or gluing.

Installation of the ring 26 is achieved by a mechanical insertion of the ring 26 into the opening 13 of side wall 12, with the application of some minimal downward and axially directed force. As previously discussed, the ring 26 and the top portion 14 of the container have a rib-and-groove fit. In other words, either one of a peripheral outer region of the ring 26 or an inner region of the top portion 14 of the side wall 12, i.e. the inner surface of the opening 13, presents a rib while the other presents a groove. There is an interference fit of one region to the other, wherein each also reinforces the other. In other words, and for example, the inserting and locking the ring 26 into the side wall 12 provides an interference fit, wherein the ring 26 reinforces the side wall 12 at the top portion 14, and the side wall 12 reinforces and helps to maintain the shape of the ring 26. The rib 17 and at least some of the surfaces defining the groove 52 form a seal and the shoulder 30 and edge 32 can help effect sealing while also limiting axial movement of the ring 26 relative to the side wall 12.

The embodiment described herein discloses a groove in the ring 26 and a rib in the container top portion 14. However, it should be understood that other configurations of the rib and groove are contemplated and within the scope of the present invention. For example, the rib may be formed on the ring 26 while the groove is located in the interior of the opening of the side wall 12. The rib and/or groove irrespective of where they are located may also be non-continuous about the perimeter of either of the ring or container surfaces. Even further, ribs and grooves may exist in an alternating pattern on each surface.

The flange 36 is first inserted into the container 10 as a leading edge. The flange 36 contacts the rib 17 of the container and displaces it outwardly somewhat towards the interior of the side wall 12 of the container 10, thus allowing the ring 26 to be inserted within the opening 13 of the side wall 12. As the ring 26 progresses into the opening of the container, the rib 17 remains compressed between the third flange 36 and the side wall 12 of the container until the shoulder 38 passes the shoulder 18 of the rib 17. At this point, the rib 17 contracts into place in the groove 52 and its shoulder 18 overlies the third shoulder 38. A feature of the present invention is that the groove 52 is dimensioned with a height H that approximates or exceeds the height H1 of the rib 17, thus permitting the shoulder 18 to be located generally in alignment with and in opposition to the shoulder 38, and within the groove 52. Interengagement between the shoulder 18, 38 prevents removal of the ring 26 from attachment to the side wall 12. Another feature is that the shoulder 30 of the ring 26 engages the edge 32 of the container, resisting any further downward motion of the ring 26 relative to the side wall 12.

The shoulder 30 is further dimensioned and shaped to rest on top of the edge 32 without appreciably extending beyond the outer face of side wall 12. In some embodiments, the ring 26 is slightly larger than the exterior surface of side wall 12. In some embodiments it is slightly larger by 0.010-0.030 inches. In other embodiments, the ring 26 is preferably flush to below flush recessed from the exterior surface of side wall 12. This permits the chime of carton 5 to be reduced to about the thickness of skirt 8 facilitating positioning of one carton 5 next to another carton 5 reducing the risk of dislodging a lid 6.

From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure. It will be understood that certain features and sub combinations are of utility and may be employed without reference to other features and sub combinations. This is contemplated by and is within the scope of the claims. Since many possible embodiments may be made of the invention without departing from the scope thereof, it is also to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

The constructions described above and illustrated in the drawings are presented by way of example only and are not intended to limit the concepts and principles of the present invention. As used herein, the terms “having” and/or “including” and other terms of inclusion are terms indicative of inclusion rather than requirement. 

1. A container comprising: a sidewall having a top portion, a top edge, a bottom portion, and a rib, the rib located in the top portion, the top portion defining an opening; a bottom wall, the bottom wall being secured to the side wall to define a storage chamber; and a ring having a generally radially extending first flange forming a first shoulder overlying the top edge of the sidewall around at least a substantial portion of the sidewall, a depending skirt inwardly of the first flange for engagement with an interior surface of the top portion, and having a second flange extending radially of the skirt and extending substantially around the skirt, the second flange forming a second shoulder, the skirt, first shoulder, and second shoulder defining a groove for cooperatively inter-engaging portions of the rib to attach the ring to the sidewall in a snap-lock fit.
 2. The container of claim 1, wherein said first shoulder is generally downwardly facing.
 3. The container of claim 2, wherein said second shoulder is generally upwardly facing and the rib having a generally downwardly facing third shoulder.
 4. The container of claim 3 wherein the ring has a mouth coextensive with the opening of the top portion.
 5. The container of claim 3 wherein the ring having a band wherein a plurality of recesses is defined around the perimeter of the band and between said band and the depending flangeskirt.
 6. The container of claim 3 wherein the rib includes a folded over portion of the side wall, the rib extending substantially around the interior perimeter of the top portion.
 7. The container of claim 1 wherein the rib is inwardly directed from the side wall and the groove is outwardly opening.
 8. The container of claim 1 wherein the bottom portion is folded inwardly forming an upwardly opening groove extending substantially around the bottom portion and the bottom wall including a depending skirt at least partially positioned in said upwardly opening groove.
 9. The container of claim wherein the ring is a rigidifying element for reinforcing the top portion having a substantial portion positioned interiorly of the top portion.
 10. The container of claim 1 wherein the first flange has an outer edge that is generally flush to below flush with an outer surface of the side wall.
 11. The container of claim 1 wherein the first flange has an outer edge that is slightly larger than an outer surface of the side wall.
 12. The container of claim 1 wherein the sidewall is generally cylindrical.
 13. The container of claim 1 wherein the sidewall includes paper board.
 14. The container of claim 12 wherein the bottom wall includes paper board.
 15. A container comprising: a wall structure defining a storage chamber, said wall structure including a sidewall with a free edge portion defining an opening communicating with the chamber; and a ring structure mounted to the sidewall adjacent the free edge portion, said ring structure including a first shoulder overlying the free edge portion limiting relative axial movement between the sidewall and ring structure, said ring structure including a depending skirt, said wall structure and depending skirt having interengaging first and second elements forming a snap lock mechanical connection between the sidewall and ring structure.
 16. A container as set forth in claim 15 wherein the first element including a first flange with a second shoulder and the second element including a rib with a third shoulder with the second and third shoulders facing one another and being interengageable.
 17. A container as set forth in claim 16 wherein the first flange and second shoulder being part of the ring structure wherein a surface of the depending skirt, the first shoulder and the second shoulder defining a groove extending at least partially around the ring structure.
 18. A container as set forth in claim 17 wherein the rib being connected to the side wall.
 19. A container as set forth in claim 18 wherein the rib extends generally radially inwardly from an inside surface of the side wall and the groove opening generally radially outwardly.
 20. A container as set forth in claim 19 wherein the rib is integral with the side wall and is a formed as a reverse fold therein.
 21. A container as set forth in claim 20 wherein the ring structure including a molded polymeric portion.
 22. A container as set forth in claim 21 wherein the skirt, first element and said first shoulder being an integral molded structure of polymeric material.
 23. A method for forming a container with a reinforcing ring, the container comprising a sidewall having a top portion, a free top edge portion, a bottom portion, and a bottom wall, the bottom wall being secured to the side wall to define a storage chamber, said method comprising; molding a ring structure for mounting to the sidewall adjacent the free edge portion, said ring structure including opposing first and second shoulders, said ring structure including a depending skirt portion between said first and second shoulders, folding the top portion of said wall structure to form a rib with a third shoulder and define a free top edge portion defining a first opening, moving a portion of said ring into said first opening whereby said rib being received in a groove defined by said skirt and first and second shoulders thereby forming a snap lock mechanical connection between the sidewall and ring structure with the first shoulder overlying the free edge portion and the third shoulder overlying the second shoulder whereby the rib is captured in the groove limiting relative longitudinal movement between the sidewall and ring structure.
 24. The method of claim 24 wherein said ring structure is inserted generally axially into the container to attach said ring to the side wall. 